Combined countersinking and counterboring attachment.



I- H. HENRY.

COMBINED COUNTERSINKING AND GOUNTERBORING ATTACHMENT.

APPLIOATION FILED JUNE 25, 1906.

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mlllllmy A ITORNE Y5 PATENTED JUNE 18, 1907.

UNITED STATES gr rnn'r OFFICE.

JOHN H. HENRY, or BRATTLEBORO, VERMONT.

Specification of Letters Patent.

Patented June 18, 1907.

Application filed June 25,1906. $erlal No. 323.355.

With these and other objects in view which will appear as the nature of the invention is better understood, the invention con sists in certain novel features of construction as hereafter fully described and claimed.

In the accompanying drawings forming a part of this specification and in which corresponding parts are denoted by like designating characters, is illustrated the preferred form of the embodiment of the invention capable of carrying the same into practical operation.

Figure 1 is a side elevation of a portion of a boring bit with the improvement attached thereto. Fig. 2 is a plan view with the boring bit in transverse section 011 the line 22 of Fig. 1. Fig. 3 is a section on the line 3-3 of Fig. 2. Fig. 4 is a perspective view of the bearing block detached. Figs. 5 and 6 are underneath perspective views from difierent points, of the cutter member detached. Fig. 7 is a bottom plan view of the cutter member.

The improved device comprises a body or block 10 having a longitudinal aperture 11 for receiving the boring bit or drill represented at 12 with one side extended in V-shape as at 13, so that the bit or drill will be always self-seating centrally of the aperture regardless of the size of the bit or drill. The bit or drill is held in position by a bearing block 1 1 movable in a socket 15 and operated by set screw 16 tapped through one of the walls of the body. The body 10 is also provided with a longitudinal aperture 17 communicating with the aperture 11 and adapted to receive the cutter member 18, one side of the cutter member having a V-shaped longitudinal channel 19 with the sides corresponding to the V-shaped portion of the aperture 11 and forming a continuation of the same. The cutter member is circular in transverse section and flattened at one side as at 20 I against which a set screw 21 bears to hold the cutter from movement in the body after it is adjusted to the desired position. T-he'cutter portion 22 of the member 18 is produced by cutting away one-half of the material transversely at one end and cutting the semi cylindrical portion which remains at an incline to the longitudinal plane of the stock of the cutter member, thus forming a cutting edge inclining away from the channel 19 and with its lower terminal next to the boring implement 12. .The body 10 is formed with a relatively large recess 27 near the operative end of the cutter member to provide for the free escape of the material severed by the cutter.

By this arrangement when the body 10 with its cutter member 18 is attached to the boring implement 12 and the latter rotated, a counter-sunk recess will be formed .inthe material when the boring has proceeded far enough to cause the cutting end of the member 18 to come into action, and by adjusting the member 18 a sufiicient distance'below the body 10, the a erture formed by the boring implement wi be counter-bored as illustrated in Fig. 3.

The upper end of the member 18 is provided with an annular channel 24, and tapped into the body 10 is a threaded stud having a lateral flange 26 fitting into the channel 24. By this arrangement when the stud. 25 is rotated by a suitable implement, the member 18 will be moved in its aperture 17 and thus adjusted to any required extent.

When the required adjustment is attained,

the member 18 may be rigidly held in position relative to the body '10 by the set screw 21, as will be obvious.

The improved device may be employed upon any size of boring implement within the range of the aperture 11, the converging sides of the aperture insuring the firm seating of the boring implement when the bearing block 14 is pressed against it by the screw 16 no matter what its diameter may be.

It will be noted that the cutting member and the adjacent side of the boring implement occupy substantially .the same relative position no matter what the size of the boring implement may be, so that the action of the cutter will be the same for all sizes of borers.

The improved device is adapted for use upon all forms of boring implements adapted for use in material requiring a counter-sunk or counter-bored outer terminal and may be employed in metal or wood as required.

The counter-sunk or counter-bored recess may be cut to any required depth Within the range of the adjusting screw 25, and by increasing the length of this screw, the depth or size of the cut may be correspondingly increased.

I-Iavin thus described the invention, What is claime is 1. A countersink comprising a body portion having a bit opening and a cutter opening which merge at adjacent sides, a cutter mounted for longitudinal adjustment in the cutter opening, the sides of Which serve as guides for the cutter, and a bit clamping block mounted for lateral movement in the body portion.

2. A countersink comprising a body portion having adjacent bit and cutter opening, a cutter located in the cutter opening, a b1t clamping block located in the body portion, said body portion having a chip exit recess communicating With the cutter opening and terminating at the outer side of the body portion.

In testimony that I claim the foregoing as my own, I have hereto affixed my signature in the presence of two Witnesses.

JOHN H. HENRY. 

